To partially suppress interference to control channels of a pico-cell from a base station apparatus of a macro-cell and enable assignment of user data to a subframe besides the same subframe using a part of control channels with interference suppressed thereto, a base station apparatus disposed in a second system having a system band comprised of a plurality of component carriers for sharing at least a part of a frequency band with a first system having a macro-cell (C2) and covering a pico-cell (C1) is configured to generate a carrier indicator for indicating another component carrier to which user data is assigned besides the same component carrier on a control channel of the component carrier, while indicating another subframe to which user data is assigned besides the same subframe on the downlink control channel.
|
11. A communication control method in a base station apparatus in a small-scale cell of a second system having a system band comprised of a single or a plurality of base frequency blocks, for sharing at least a part of a frequency band with a first system having a large-scale cell and covering a small-scale cell, wherein the communication control method comprising:
generating indication information for a number of subframes, each subframe assigned individually to each of the plurality of the base frequency blocks constituting the system band of the second system, indicating another subframe to which user data is assigned besides a same subframe on a downlink control channel; and
generating a transmission frame including the indication information.
17. A communication control method in a base station apparatus in a second system having a system band comprised of a single or a plurality of base frequency blocks, for sharing at least a part of a frequency band with a first system having a small-scale cell and covering a large-scale cell, wherein the communication control method comprising:
generating indication information for a number of subframes, each subframe assigned individually to each of the plurality of the base frequency blocks constituting the system band of the second system, indicating assignment of user data to another subframe in which a downlink control channel is not used besides a same subframe on a downlink control channel; and
generating a transmission frame including the indication information.
1. A base station apparatus in a small-scale cell of a second system having a system band comprised of a single or a plurality of base frequency blocks, for sharing at least a part of a frequency band with a first system having a large-scale cell and covering the small-scale cell, wherein the base station apparatus comprising:
an indication information generating section configured to generate indication information for a number of subframes, each subframe assigned individually to each of the plurality of the base frequency blocks constituting the system band of the second system, indicating another subframe to which user data is assigned besides a same subframe on a downlink control channel; and
a transmission frame generating section configured to generate a transmission frame including the indication information.
6. A mobile terminal apparatus that communicates via a second system having a system band comprised of a single or a plurality of base frequency blocks, for sharing at least a part of a frequency band with a first system having a large-scale cell and covering a small-scale cell, wherein the mobile terminal apparatus comprising:
an indication information acquiring section configured to acquire, from a base station apparatus, indication information for a number of subframes, each subframe assigned individually to each of the plurality of the base frequency blocks constituting the system band of the second system, indicating another subframe to which user data is assigned besides a same subframe on a downlink control channel; and
a data demodulation section configured to demodulate the user data based on the indication information.
12. A base station apparatus in a second system having a system band comprised of a single or a plurality of base frequency blocks, for sharing at least a part of a frequency band with a first system having a small-scale cell and covering a large-scale cell, wherein the base station apparatus comprising:
an indication information generating section configured to generate indication information for a number of subframes, each subframe assigned individually to each of the plurality of the base frequency blocks constituting the system band of the second system, indicating assignment of user data to another subframe in which a downlink control channel is not used besides a same subframe on a downlink control channel; and
a transmission frame generating section configured to generate a transmission frame including the indication information.
16. A mobile terminal apparatus that communicates via a second system having a system band comprised of a single or a plurality of base frequency blocks, for sharing at least a part of a frequency band with a first system having a small-scale cell and covering a large-scale cell, wherein the mobile terminal apparatus comprising:
an indication information acquiring section configured to acquire, from a base station apparatus, indication information for a number of subframes, each subframe assigned individually to each of the plurality of the base frequency blocks constituting the system band of the second system, indicating assignment of user data to another subframe in which a downlink control channel is not used besides a same subframe on a downlink control channel; and
a data demodulation section configured to demodulate the user data based on the indication information.
2. The base station apparatus according to
3. The base station apparatus according to
4. The base station apparatus according to
5. The base station apparatus according to
7. The mobile terminal apparatus according to
8. The mobile terminal apparatus according to
9. The mobile terminal apparatus according to
10. The mobile terminal apparatus according to
13. The base station apparatus according to
14. The base station apparatus according to
15. The base station apparatus according to
18. The base station apparatus according to
19. The base station apparatus according to
20. The mobile terminal apparatus according to
21. The mobile terminal apparatus according to
22. The base station apparatus according to
|
The present invention relates to a base station apparatus, mobile terminal apparatus and communication control method in the next-generation mobile communication system.
In UMTS (Universal Mobile Telecommunications System) networks, for the purpose of improving spectral usage efficiency and further improving data rates, by adopting HSDPA (High Speed Downlink Packet Access) and HSUPA (High Speed Uplink Packet Access), it is performed exploiting maximum features of the system based on W-CDMA (Wideband Code Division Multiple Access). For the UMTS network, for the purpose of further increasing high-speed data rates, providing low delay and the like, Long Term Evolution (LTE) has been studied (Non-patent Literature 1). In LTE, as a multiplexing scheme, OFDMA (Orthogonal Frequency Division Multiple Access) different from W-CDMA is used in downlink, while SC-FDMA (Single Carrier Frequency Division Multiple Access) is used in uplink.
In the 3G system, a fixed band of 5 MHz is substantially used, and it is possible to achieve transmission rates of approximately maximum 2 Mbps in downlink. Meanwhile, in the LTE system, using variable bands ranging from 1.4 MHz to 20 MHz, it is possible to achieve transmission rates of maximum 300 Mbps in downlink and about 75 Mbps in uplink. Further, in the UMTS network, for the purpose of further increasing the wide-band and high speed, successor systems to LTE have been studied (for example, LTE Advanced (LTE-A)). In LTE-A (LTE Release 10), a Heterogeneous network configuration is studied in which importance is attached to a local area environment in addition to conventional cellular environments.
The present invention was made in view of such a respect, and it is an object of the invention to provide a base station apparatus, mobile terminal apparatus and communication control method for enabling control adapted to interference inside a Heterogeneous network to be performed to support the next-generation mobile communication system.
A base station apparatus of the invention is a base station apparatus disposed in a second system having a system band comprised of a single or a plurality of base frequency blocks, for sharing at least a part of a frequency band with a first system having a large-scale cell and covering a small-scale cell and is characterized by having an indication information generating section configured to generate indication information for indicating another base frequency block to which user data is assigned besides the same base frequency block on a downlink control channel of the base frequency block, while indicating another subframe to which user data is assigned besides the same subframe on the downlink control channel, and a transmission frame generating section configured to generates a transmission frame including the indication information.
According to the invention, it is possible to assign user data to another subframe indicated by the indication information besides the same subframe on the downlink control channel. Accordingly, by indicating a subframe of a control channel that undergoes interference from the first system using the indication information, it is possible to assign user data of the subframe that undergoes interference on the control channel of the subframe that does not undergo interference. Further, another subframe to which user data is assigned besides the same subframe is indicated using the indication information for indicating another base frequency block to which user data is assigned besides the same base frequency block on the control channel, and it is thereby possible to make the control configuration simplified.
For example, in
In addition, in the LTE-A system, a Heterogeneous network (hereinafter, referred to as HetNet) configuration is studied in which importance is attached to a local area environment. As shown in
Accordingly, when the macro-cell C2 and the pico-cell C1 are operated with close frequency bands, as shown in
To solve the problems, as shown in
However, in the aforementioned method, in subframes except the subframes enclosed by dashed lines of the pico-cell C1, the control channel undergoes interference from the radio frame of the macro-cell C2. The control channel of the downlink radio frame is used to transmit scheduling information of the data channel (PDSCH) in the same subframe, etc. i.e. assign user data in the same subframe. Therefore, when the downlink control channel undergoes interference, there is a problem that it is not possible to assign (schedule) user data in the same subframe.
Therefore, to solve the problem, the inventors of the invention arrived at the invention. In other words, it is the gist of the invention to suppress interference from the base station apparatus of a macro-cell partially to control channels of a pico-cell, and enable assignment of user data to subframes besides the same subframe using a part of control channels with interference suppressed thereto.
An Embodiment of the invention will specifically be described below with reference to accompanying drawings.
As shown in
Meanwhile, a downlink radio frame of the pico-cell C1 has the same radio frame configuration as the downlink radio frame of the macro-cell C2, but the subframe is not set for the blank period. Further, the downlink radio frame of the pico-cell C1 is subframe-shifted in the time-axis direction relatively to the radio frame of the macro-cell C2. By this means, a part of control channels, broadcast channels, synchronization signals and the like in the downlink radio frame of the pico-cell C1 are made coincident with the blank periods of the downlink radio frame of the macro-cell C2, and interference from the macro-cell C2 is suppressed. In this Embodiment, a part of control channels with interference suppressed thereto transmit scheduling information of data channels (PDSCHs) as a substitute for control channels to which interference is not suppressed.
For example, in the downlink radio frame of the pico-cell C1, a control channel of a subframe #1 corresponds to the blank period of the downlink radio frame of the macro-cell C2, and does not undergo interference from the macro-cell C2. The control channel of the subframe #1 transmits scheduling information of not only the data channel of the same subframe but also the data channel of a subframe #2 as a substitute for the control channel of the adjacent subframe #2 undergoing interference from the macro-cell C2. Thus, in the radio frame of the pico-cell C1, the control channel performs assignment of user data to not only the same subframe but also the adjacent subframe.
In addition, the control channel is capable of performing assignment of user data to not only the adjacent subframe but also a subsequent subframe. For example, in the downlink radio frame of the pico-cell C1, a control channel of a subframe #4 corresponds to the blank period of the radio frame of the macro-cell C2, and does not undergo interference from the macro-cell C2. In this case, the control channel of the subframe #4 transmits scheduling information of not only the data channel of the same subframe but also the data channel of a subframe #7 as a substitute for the control channel of the subframe #7 which is 3 subframes later and undergoes interference from the macro-cell C2.
Such assignment of user data to a plurality of subframes by the downlink control channel is performed using a carrier indicator (CI). Herein, the carrier indicator will be described briefly. In LTE-A, the band is broadened using a plurality of component carriers, and cross-carrier scheduling is considered. As shown in
In this case, a carrier indicator of 3 bits as indication information is added to downlink control information (DCI) transmitted on the downlink control channel. The carrier indicator enables the downlink control channel to indicate another component carrier to which user data is assigned besides the same component carrier. By using this carrier indicator, the mobile terminal apparatus receives the downlink control information on the downlink control channel of a single component carrier, and receives downlink user data on downlink data channels of respective component carriers. In this Embodiment, the interpretation of the carrier indicator is modified, and it is made possible to perform assignment of user data to not only the same subframe but also a subsequent subframe by the control channel.
The interpretation methods of the carrier indicator will be described with reference to
As shown in
As shown in
Corresponding to a determination result of the first bit, the second and third bits are interpreted as index bits to identify a carrier index (base frequency block index) associated with each component carrier or a subframe index associated with each subframe. In addition, the carrier index associated with each component carrier may be fixed information assigned to each component carrier, or relative information to a component carrier that is the reference. Meanwhile, the subframe index associated with each subframe may be fixed information assigned to each subframe, or relative information to a subframe that is the reference. Accordingly, as in the first interpretation method, the subframe index is capable of being interpreted as the number of subframes between a subframe of a downlink control channel and another subframe to which user data is assigned by the control channel.
The second and third bits indicate a carrier index of a component carrier when the carrier indicator is determined as for carrier indication. Meanwhile, the second and third bits indicate a subframe index of a subframe when the carrier indicator is determined as for subframe indication. Thus, by combining the first bit and the second and third bits, it is possible to use the carrier indicator for carrier indication and for subframe indicator differently.
The carrier indicator is added for each downlink control information. By this means, on a single control channel, it is possible to distinguish between downlink control information for a plurality of subframes to transmit. In addition, the carrier indicator is not limited to the first and second interpretation methods as described above, and any interpretation method may be applied as long as the method is of configuration for indicating another subframe to which user data is assigned besides the same subframe on a downlink control channel.
In addition, it may be configured to beforehand notify a mobile terminal apparatus of information to interpret the carrier indicator by the first interpretation method or the second interpretation method. In this case, the base station apparatus is capable of changing the correspondence relationship between the carrier indicator, and the subframe and component carrier. Further, the mobile terminal apparatus may be configured to store the correspondence relationship between the carrier indicator, and the subframe and component carrier in a fixed manner.
In addition, as shown in
For example, in the downlink radio frame of the macro-cell C2, the control channel of the subframe #2 is set for off to suppress interference to the downlink radio frame of the pico-cell C1. As a substitute for the control channel of the subframe #2, the control channel of the subframe #1 of the macro-cell C2 transmits the scheduling information of the data channel of the subframe #2. Thus, in the radio frame of the macro-cell C2, the control channel is configured to enable user data to be assigned to not only the same subframe but also to a subsequent subframe.
Referring to
As shown in
In addition, the carrier index described herein may be fixed information assigned to each component carrier, or relative information to a component carrier that is the reference. Meanwhile, the subframe index associated with each subframe may be fixed information assigned to each subframe, or relative information to a subframe that is the reference. Accordingly, the subframe index is capable of being interpreted as the number of subframes between a subframe of a downlink control channel and another subframe to which user data is assigned by the control channel.
For example, in the carrier indicator, the case of “000” is interpreted as assignment of user data to the present subframe of the component carrier CC#1. Meanwhile, in the carrier indicator, the case of “101” is interpreted as assignment of user data to the subframe #2 of the component carrier CC#2. Accordingly, the carrier indicator added to the downlink control information enables assignment of user data to another subframe besides the same subframe by the control channel.
In addition, it may be configured to beforehand notify a mobile terminal apparatus of information to indicate the correspondence relationship between the carrier indicator, and the subframe and component carrier. In this case, the base station apparatus is capable of changing the correspondence relationship between the carrier indicator, and the subframe and component carrier. Further, the mobile terminal apparatus may be configured to store the correspondence relationship between the carrier indicator, and the subframe and component carrier in a fixed manner.
Herein, a radio communication system according to the Embodiment of the invention will be described specifically.
As shown in
In the radio communication system 1, as a radio access scheme, OFDMA (Orthogonal Frequency Division Multiple Access) is applied in downlink, while SC-FDMA (Single-Carrier Frequency Division Multiple Access) is applied in uplink. OFDMA is a multicarrier transmission scheme for dividing a frequency band into a plurality of narrow frequency bands (subcarriers), and mapping data to each subcarrier to perform communications. SC-FDMA is a single-carrier transmission scheme for dividing the system band into bands comprised of a single or consecutive resource blocks for each terminal so that a plurality of terminals uses mutually different bands, and thereby reducing interference among the terminals.
Described herein are communication channels in the LTE system. Communication channels in downlink have the PDSCH as a downlink data channel shared among mobile terminal apparatuses, and downlink L1/L2 control channels (PDCCH, PCFICH, PHICH). User data and higher control information is transmitted on the PDSCH. Scheduling information of the PDSCH and PUSCH and others are transmitted on the PDCCH. The number of OFDM symbols used in the PDCCH is transmitted on the PCFICH (Physical Control Format Indicator Channel). ACK/NACK of HARQ (Hybrid Automatic Repeat reQuest) to the PUSCH is transmitted on the PHICH (Physical Hybrid-ARQ Indicator Channel).
Uplink communication channels have the PUSCH (Physical Uplink Shared Channel) as an uplink data channel shared among mobile terminal apparatuses, and the PUCCH (Physical Uplink Control Channel) that is an uplink control channel. User data and higher control information is transmitted on the PUSCH. Further, downlink radio quality information (CQI: Channel Quality Indicator), ACK/NACK and others are transmitted on the PUCCH.
Referring to
The base station apparatus 20 is provided with a transmission/reception antenna 201, amplifying section 202, transmission/reception section 203, baseband signal processing section 204, call processing section 205 and transmission path interface 206. The user data transmitted from the base station apparatus 20 to the mobile terminal apparatus 10 in downlink is input to the baseband signal processing section 204 via the transmission path interface 206 from the upper station apparatus.
The baseband signal processing section 204 performs, on a signal of the downlink data channel, PDCP layer processing, segmentation and concatenation of the user data, RLC (Radio Link Control) layer transmission processing such as transmission processing of RLC retransmission control, MAC (Medium Access Control) retransmission control e.g. transmission processing of HARQ, scheduling, transmission format selection, channel coding, Inverse Fast Fourier Transform (IFFT) processing and precoding processing. Further, with respect to a signal of the downlink control channel, the transmission processing such as channel coding and Inverse Fast Fourier Transform is also performed. Furthermore, on the broadcast channel, the baseband signal processing section 204 notifies the mobile terminal apparatuses 10 connected to the same cell C1 of control information for each mobile terminal apparatus 10 to perform radio communications with the base station apparatus 20.
The transmission/reception section 203 converts the frequency of the baseband signal output from the baseband signal processing section 204 into a radio frequency band. The amplifying section 202 amplifies the transmission signal with the frequency converted to output to the transmission/reception antenna 201.
Referring to
The mobile terminal apparatus 10 is provided with a transmission/reception antenna 101, amplifying section 102, transmission/reception section 103, baseband signal processing section 104 and application section 105. With respect to transmission data in downlink, a radio frequency signal received in the transmission/reception antenna 101 is amplified in the amplifying section 102, subjected to frequency conversion in the transmission/reception section 103, and is converted into a baseband signal.
The baseband signal processing section 104 performs, on the baseband signal, FFT processing, error correcting decoding, reception processing of retransmission control, etc. Among the data in downlink, user data in downlink is transferred to the application section 105. The application section 105 performs processing concerning layers higher than the physical layer and MAC layer and the like. Further, among the data in downlink, broadcast information is also transferred to the application section 105.
Referring to
As shown in
The downlink control information generating section 212 determines a carrier indicator corresponding to each of the component carriers indicated by the scheduler 211. In this case, the first bit of the carrier indicator is set at “0” indicating for component carrier indication, and the second and third bits are set at a carrier index indicated by the scheduler 211.
Further, the downlink control information generating section 212 assigns user data (PDSCH) to each mobile terminal apparatus 10 to a predetermined assignment frequency using the sub-band index indicated by the scheduler 211. Thus, the downlink control information generating section 212 determines the component carrier to assign the user data to the mobile terminal apparatus 10, and the assignment frequency of the user data in the component carrier by indication of the scheduler 211, and generates the downlink control information.
In the example as shown in
Further, in scheduling user data for another subframe besides the same subframe on the downlink control channel, the scheduler 211 indicates a subframe index and a sub-band index to the downlink control information generating section 212. In this case, the scheduler 211 discriminates between a control channel that undergoes interference from the macro-cell C2 and a control channel that does not undergo the interference for each subframe. This discrimination of control channels is performed based on the shift amount in the time-axis direction of radio frames of the pico-cell C1 and the macro-cell C2, and a blank position of the radio frame of the macro-cell C2. The scheduler 211 judges a control channel corresponding to the blank period of the radio frame from the macro-cell C2 as undergoing interference from the macro-cell C2, while judging the other control channels as not undergoing the interference.
Then, in generating the downlink control information of the downlink control channel that does not undergo interference from the macro-cell C2, the scheduler 211 indicates subframe indexes of the corresponding subframe and a subsequent subframe of the downlink control channel that undergoes interference. For example, in
The downlink control information generating section 212 determines a carrier indicator corresponding to each of the subframes indicated by the scheduler 211. In this case, the first bit of the carrier indicator is set at “1” indicating for subframe indication, and the second and third bits are set at a subframe index indicated by the scheduler 211.
Further, the downlink control information generating section 212 assigns user data (PDSCH) to each mobile terminal apparatus 10 to a predetermined assignment frequency using the sub-band index indicated by the scheduler 211. Thus, the downlink control information generating section 212 determines the subframe to assign the user data to the mobile terminal apparatus 10, and the assignment frequency in the subframe by indication of the scheduler 211, and generates the downlink control information.
In the example as shown in
The transmission frame generating section 213 multiplexes the downlink control information and user data (PDSCH), and applies the other transmission processing to generate a downlink transmission frame.
Referring to
As shown in
Based on the subframe index, carrier index and sub-band index, the downlink data channel demodulation section 112 demodulates the user data from the transmission frame. For example, at the time of cross-carrier scheduling, the user data is demodulated using the carrier index and the sub-band index. Further, at the time of scheduling of the user data to another subframe besides the same subframe on the downlink control channel, the user data is demodulated using the subframe index and the sub-band index.
In addition, in the above-mentioned process of generating a transmission frame and the process of receiving the transmission frame, described is the configuration in which the second interpretation method is applied to the carrier indicator, but the invention is not limited this configuration, and for example, a configuration in which the first interpretation method is applied may be adopted.
Referring to
As shown in
Further, in generating downlink control information of a downlink control channel that is not set for off, the scheduler 411 indicates subframe indexes of the corresponding subframe and a subsequent subframe with the downlink control channel set for off. For example, in
The downlink control information generating section 412 determines a carrier indicator using the carrier index and the subframe index indicated by the scheduler 411. In this case, the carrier indicator is determined from the correspondence relationship between the carrier index and the subframe index as shown in
Further, the downlink control information generating section 412 assigns user data (PDSCH) to each mobile terminal apparatus 30 to a predetermined assignment frequency using the sub-band index indicated by the scheduler 411. Thus, the downlink control information generating section 412 determines the component carrier to which the user data to the mobile terminal apparatus 30 is assigned, subframe and the assignment frequency by indication of the scheduler 411, and generates the downlink control information. The downlink control information generated in the downlink control information generating section 412 is input to the transmission frame generating section 413.
The transmission frame generating section 413 multiplexes the downlink control information and user data (PDSCH), and applies the other transmission processing to generate a downlink transmission frame.
Referring to
As shown in
Based on the subframe index, carrier index and sub-band index, the downlink data channel demodulation section 312 demodulates the user data from the transmission frame.
As described above, according to the base station apparatus 20 according to this Embodiment, it is possible to assign user data to another subframe indicated by the carrier indicator besides the same subframe on the downlink control channel. Accordingly, by indicating a subframe of a control channel that undergoes interference from the first system using the carrier indicator, it is possible to assign user data of the subframe that undergoes interference on the control channel of the subframe that does not undergo interference. Further, another subframe to which user data is assigned besides the same subframe is indicated using the carrier indicator, and it is thereby possible to make the control configuration simplified.
In addition, the aforementioned Embodiment describes the base station apparatus that covers the pico-cell as a small-scale cell, but the invention is not limited to this configuration. It is essential only that the base station apparatus covers a cell that undergoes interference from the macro-cell, and the base station apparatus may be small-sized base station apparatuses that cover a femto-cell, micro-cell and the like.
Further, in the above-mentioned Embodiment, the blank period indicates a period during which the radio frame of the pico-cell is not affected by interference from the radio frame of the macro-cell. In the radio frame of the macro-cell, the blank period may be a period during which no data is transmitted, or may be defined as a period during which data is transmitted to the extent that does not affect interference. Further, in the radio frame of the macro-cell, the blank period may be defined as a period during which transmission is performed with transmission power of the extent that does not have any effect of interference on the radio frame of the pico-cell. Furthermore, in the radio frame of the macro-cell, the blank period may be defined as a period during which transmission is performed with an interfering amount of the extent that does not affect the radio frame of the pico-cell.
Furthermore, in the above-mentioned Embodiment, such a configuration may be adopted in which the base station apparatus of the pico-cell receives signaling of the base statin apparatus of the macro-cell, alternatively, the reverse may be possible. Still furthermore, in using the MBSFN subframe, the base station apparatus of the macro-cell is configured to notify the base station apparatus of the pico-cell of the blank position.
The present invention is not limited to the above-mentioned Embodiment, and is capable of being carried into practice with various modifications thereof. For example, without departing from the scope of the invention, assignment of component carriers, the number of processing sections, processing procedures, the number of component carriers, and the number of aggregated component carriers in the above-mentioned description are capable of being carried into practice with modifications thereof as appropriate. Further, the invention is capable of being carried into practice with modifications thereof as appropriate without departing from the scope of the invention.
The present application is based on Japanese Patent Application No. 2010-087390 filed on Apr. 5, 2010, entire content of which is expressly incorporated by reference herein.
Abe, Tetsushi, Nagata, Satoshi, Miki, Nobuhiko, Jaturong, Sangiamwong
Patent | Priority | Assignee | Title |
Patent | Priority | Assignee | Title |
8149825, | Oct 05 1995 | AVAGO TECHNOLOGIES GENERAL IP SINGAPORE PTE LTD | Hierarchical data collection network supporting packetized voice communications among wireless terminals and telephones |
8406795, | Jun 13 2005 | Qualcomm Incorporated | Methods and apparatus for performing timing synchronization with base stations |
8488534, | Mar 20 2007 | NTT DoCoMo, Inc | Base station, user device, transmission method, and reception method |
20090092090, |
Executed on | Assignor | Assignee | Conveyance | Frame | Reel | Doc |
Apr 05 2011 | NTT DOCOMO, INC. | (assignment on the face of the patent) | / | |||
Sep 26 2012 | ABE, TETSUSHI | NTT DoCoMo, Inc | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 029437 | /0652 | |
Sep 26 2012 | MIKI, NOBUHIKO | NTT DoCoMo, Inc | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 029437 | /0652 | |
Sep 26 2012 | NAGATA, SATOSHI | NTT DoCoMo, Inc | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 029437 | /0652 | |
Sep 26 2012 | JATURONG, SANGIAMWONG | NTT DoCoMo, Inc | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 029437 | /0652 |
Date | Maintenance Fee Events |
Mar 23 2015 | ASPN: Payor Number Assigned. |
Oct 05 2017 | M1551: Payment of Maintenance Fee, 4th Year, Large Entity. |
Dec 13 2021 | REM: Maintenance Fee Reminder Mailed. |
May 30 2022 | EXP: Patent Expired for Failure to Pay Maintenance Fees. |
Date | Maintenance Schedule |
Apr 22 2017 | 4 years fee payment window open |
Oct 22 2017 | 6 months grace period start (w surcharge) |
Apr 22 2018 | patent expiry (for year 4) |
Apr 22 2020 | 2 years to revive unintentionally abandoned end. (for year 4) |
Apr 22 2021 | 8 years fee payment window open |
Oct 22 2021 | 6 months grace period start (w surcharge) |
Apr 22 2022 | patent expiry (for year 8) |
Apr 22 2024 | 2 years to revive unintentionally abandoned end. (for year 8) |
Apr 22 2025 | 12 years fee payment window open |
Oct 22 2025 | 6 months grace period start (w surcharge) |
Apr 22 2026 | patent expiry (for year 12) |
Apr 22 2028 | 2 years to revive unintentionally abandoned end. (for year 12) |